The present invention relates to mud flaps for trucks and more particularly to a retractable mud flap assembly for the purpose of relocating the mud flap, from its operational position behind the rear wheels, to an alternate position less susceptible to damage caused by, the mud flap being caught beneath the wheels when the truck is backed over rough terrain, or the mud flap being pinched between the wheels and a dumped load or other piece of equipment.
The laws of many states as well as federal law requires the mandatory use of mud flaps on trucks while on the highway. Such flaps are necessary to protect other vehicles and persons from mud and materials being thrown to the rear of the vehicle incident to wheel rotation.
Several instances exist which will cause these mud flaps to become damaged or torn completely from the vehicle. These instances include backing the truck over rough terrain such that the mud flap is caught beneath the rear wheels as the wheels sink into soft ground. Another instance is when the mud flaps become buried in the material dumped from a dump truck. As the dump truck is driven away the mud flaps remain and are torn from the vehicle. Another instance is when the truck is mated with some other piece of equipment, such as a paver. When the combined unit is moved, the mud flaps may become entangled between the wheels and the coupled equipment such that the mud flap is torn from the vehicle.
A review of prior art therefore reveals attempts to eliminate this problem and several differing approaches have been proposed. Case, U.S. Pat. No. 2,935,366 and Manning, U.S. Pat. No. 5,044.677 describe mud flap retaining methods whereby the mud flap is easily removed and replaced to prevent damage or to facilitate the replacement of a mud flap when necessary due to damage or loss.
Barrett, U.S. Pat. No. 2,872,211 describes a method whereby the mud flap is pivoted from it""s operative position, transverse to the longitudinal axis of the truck behind the rear wheels, to a position parallel the longitudinal axes of said truck and alongside the rear wheels, at the outer edge of the truck. Due to the outward pivoting of the mud flap, during operation, this mechanical device requires additional clearance around the portion of the truck where the mud flap relocation is occurring. In tight quarters it may not be possible to properly relocate the mud flap and extreme care must be taken to insure that persons in the immediate vicinity of the truck not be struck and injured by the operation of said device.
Fusco, U.S. Pat. No. 4,033,599 and Knowley, U.S. Pat. No. 4,541,646 also describe pivoting mud flap mounting devices however these two devices pivot the mud flap inward, stowing the mud flap parallel to the rear of said truck in the area between the rear wheels where it is less likely to become damaged. Both of these devices require the operator to manually relocate the mud flap to the desired position. While in the stowed position these devices do offer some protection from damage caused by the truck""s wheel during a backing operation, these devices do not offer protection from damage caused by materials being dumped from the truck or damage caused by other equipment that may be coupled to the rear of the truck.
Various flap retraction systems have been proposed. The aim of these devices is to effectively shorten the mud flap thus eliminating the portion of the mud flap which could become entangled with the wheels, the dumped load, or other equipment coupled to the rear of the truck.
Saxton U.S. Pat. No. 3,165,360; Hartling, U.S. Pat. No. 3,203,710; Moore, U.S. Pat. No. 3,582,109; and Cole U.S. Pat. No. 3,806,196; attempt to achieve this goal by raising the lower portion of the mud flap thereby causing it to fold in half. These design all require the use of cables or other lifting mechanisms attached to the lower portion of the mud flap, where they themselves are subject to damage and entanglement. Additionally, the mounting of these devices is truck specific; that is each type of truck requires a slightly differing design to ensure that the mud flap is raised to the proper position and that the lifting mechanism does not interfere with the operation of the vehicle.
Zerby, U.S. Pat. No. 2,981,553 proposes to use cables and pulleys to pivot the entire mud flap to a horizontal plane by attaching a cable to the bottom of the mud flap through a pulley which is affixed to the truck frame above and behind the aforementioned mud flap. Because the location of the pulley must be some distance to the rear of the mud flap this system can not be installed on trucks that have their rear most wheels located close to the rear of the truck. This system will also suffer from the ills associated with cables attached to the lower portion of the mud flap and pulleys which are subject to damage, misalignment, and have truck specific mounting requirements.
France, U.S. Pat. No. 3,794,383 proposed a retraction device which raises the entire mud flap through use of cables and pulleys, activated by the dumping truck body or other mechanical means. These systems with the array of pulleys and cables require truck specific mounting, and are easily damaged as material snags or entangles the apparatus, and dirt or debris fowls the system.
Overend, U.S. Pat. No. 3,580,604 and Kayazek U.S. Pat. No. 3,806,197 propose that two short mud flaps be employed, one hanging below the other to achieve the desired overall length, and a retraction device designed to lift only the lower mud flap be employed to a raise this lower mud flap to a location where interferences will not occur. These devices use steel supports and springs or cables to hold the lower flap in position and relocate the mud flap to the raised position. These supports are easily damaged by equipment contacting the rear of the truck leaving the device inoperable. Another disadvantage is that this installation is also truck specific, that is each truck will require a different design to properly position the mud flaps.
Anderson, U.S. Pat. No. 5,582,431 proposes a mud flap retraction device consisting of an enclosure located above the rear wheels in which the mud flap is retracted using a hydraulic cylinder. The suspension design of many truck is such that the vertical travel of the rear wheels extends upward into a wheel well designed into the truck body. This device, located directly above the rear wheels limits the effective suspension travel and could be easily damaged by the upward movement of the rear wheels during their normal travel.
A principal object of the invention is to provide a retractable mud flap system whereby the mud flaps, operationally disposed behind the vehicle, may be retracted to an alternate, out of the way, position, under operating conditions which might cause those particular mud flaps to be damaged or destroyed.
Another object is to provide a retractable mud flap system that is simple in construction and accordingly economical to build and may be easily installed on all existing trucks or installed as new equipment on yet to be built vehicles.
Another object is to provide a retractable mud flap system that protects the mud flap from damage when retracted while eliminating the need for springs, cables, and pulleys attached to the truck body, or specially constructed mud flaps.
Another object is to provide a retractable mud flap system that is reliable, durable, and trouble free. One that will not become inoperable despite the effects of dirt, grime, and mud under the truck, and will not be subject to damage by debris, contact with moving parts of the vehicle, or contact with other equipment associated with the use of the truck.
Another object is to provide a retractable mud flap system that can be operated automatically or manually from the drivers compartment for the truck.
Further objects and advantages will be apparent, to those skilled in the art, from the following detailed descriptions, claims, and accompanying drawings which illustrate a preferred embodiment of the invention.